Flexible coupling for exhaust conduits of internal-combustion engines



July 8, 1947. MERGER 2,423,462

FLEXIBLE COUPLING FOR EXHAUST CONDUITS OF INTERNAL-COMBUSTION ENGINESOriginal Filed May 4, 1943 INVENTOR 'JJerre LFnesifierakr ATTORNEYPatented July 8, 1 947 FLEXIBLE COUPLING FOR EXHAUST GONDUITS OFINTERNAL-COMBUS- TION ENGINES Pierre Ernest Mercier, Neuilly, FranceOriginal application May 4, 1943, Serial No. 485,593. Divided and thisapplication November 28, 1945, Serial No. 631,362

1 Claim. 1

This invention relates to an improved coupling, and particularly to aflexible coupling adapted for use in establishing a, fluid typeconnection in exhaust pipes or between the exhaust manifold and theexhaust pipe of an internal combustion engine, such as is used, forexample, in aeroplanes and other vehicles where the coupling and thejoined conduits are subjected to extremes of temperature variations andalso to vibrations when in use.

It is an object of the invention to provide a flexible coupling whichmay be readily dismantled and reassembled without expensive and tediouswelding or riveting operations.

It is a further object of the invention to provide a flexible couplingthat functions to maintain an effective sealing connection betweenadjacent ends of sections of a conduit through a wide range oftemperature conditions such as are encountered in engine operation.

Other objects and advantages of the invention will become apparent asthe description proceeds.

The single figure of the drawing illustrates a longitudinal sectionthrough the coupling and the ends of two sections of a conduit that areto be joined thereby.

As shown in the drawing, the coupling l8 is used to connect two pipes 35and 36, the ends 35a and 36a of which are shown as spaced a shortdistance from one another to permit of pivoting action between the twopipes and also for lengthwise expansion. The coupling consists of threemain parts, namely a cylindrical collar 31 attached adjacent one end tothe pipe 35 by welding, riveting or other suitable means. The mainportion 31a is free and, is slightly spaced concentrically from theouter surface of the pipe 35, forming therebetween an annular slot inwhich is received the end of a sealing collar 38 having at one end acylindrical portion 380. adapted to snugly fit about the end of the pipe35. This cylindrical portion merges into a slightly outwardly flaredportion 381) which continues to expand until it is turned b-ackwardly at39 to form a locking ring 40.

Fixed to the pipe 36 at 4| there is a bell-shaped member 42. This memberis joined adjacent its outer end to an inwardly directed annular strip44, which is slightly spaced from the member 42 on its side nearest thepipe 36, thereby forming a sealing groove 45. When assembeld to form ajoint or coupling, the turned back portion 39 of the sealing collar 38is snugly fitted in the sealing groove 45 and at the other end theportion 38a is snugly received in the annular groove between the member31a and the end of the pipe 35. The end of the collar 31 is flaredoutwardly at 46 to provide a thin cooling fin 41. In a similar mannerthe outwardly extending rim portion 43 of the member 42 serves to act asa cooling fin rapidly giving up heat to passing air and establishing amarked temperature gradient between the temperature of the gases passingthrough the pipe and the temperature at the rim 43.

Besides functioning to facilitate transfer of heat from the hot exhaustgases to the passing air, which may be circulated by means of a fan orother means, either solely for cooling purposes or to transfer heat fromthe exhaust gases to the incoming air used to maintain combustion of thefuel introduced into the engine cylinders, the structural arrangementillustrated serves the further important purpose of causing the sealingcollar 38 to be sealed more tightly at its two ends during operation ofthe engine than during intervals when the engine is idle. This resultmay be visualized when it is borne in mind that as the collars areheated by the exhaust gases they will tend to expand more rapidly in theareas closer to the pipes 35 and 36 than in the outer areas where thecooling air has a chance to pass over the extended fin surfaces. Becauseof the unequal expansion, there will be a tendency for the free end ofthe strip 44 to toe pivoted counterclockwise and press closer againstthe locking ring 45. Likewise the cooling fin 41 and the adjacentportions of the collar 31 will tend to expand less than the portionsthereof closer to the connection with the end of the pipe 35. This willtend to cause the free end of the collar 31 to bear closer against thesealing member 38 at or adjacent the pivotal axis of the coupling, whichis indicated at 48 in the drawing as located at a point in thelongitudinal axes of the pipes 35 and 36 and approximately equi-distantfrom the adjacent ends of these pipes.

The coupling I8 will generally be made of relatively light gauge sheetmetal, thus facilitating the transmission of heat to passing air toy thefins and at the same time emphasizing the heat gradient between thesefins and the temperature of the main portions of the elements of whichthese fins are a part. As a consequence a deforming action isestablished which promotes the sealing contact between the loose sealingcollar and the adjacent attached collars.

It will be apparent that my improved coupling has the further advantagethat it may be easily assembled without recourse to welding, riveting 0rbolting, and that it may be quickly dismantled 3 when the engine is tobe taken down for repairs or overhauling.

Although I have emphasized the pivoting action in the coupling, it willbe understood that it has the additional attribute of permittingconsiderable lengthwise expansion and contraction without setting upundesired stresses in the pipes or joints thereof with the manifold ofan internal combustion engine or with the flange connection to an engineexhaust port.

The coupling and the associations thereof in an exhaust manifoldassembly may be modified in various respects without departing from thescope of the invention, which is not to be deemed as limited otherwisethan as limited by the scope of the appended claim.

The instant application is a division of application Serial No. 485,593,filed May 4, 1943, now Patent No. 2,388,924, dated November 13, 1945.

I claim:

In a flexible coupling for engine exhaust coriduits and the like, a pairof fixed collars respectively secured at one end adjacent one end of thetwo pipes to be joined and at their other ends flared outwardly awayfrom said pipes, said members having their flared ends extendinggenerally toward one another when the ends of the pipes are brought intoproximity to one another and a third collar member having a cylindricalportion at one end adapted to be brought into a press fit engagementbetween the end of one of said pipes and the collar fixed thereto andhaving its other end flared first gradually outwardly and thenbackwardly, said backwardly turned portion being adapted to be broughtinto interlocking sealing engagement with a cooperating outwardly flaredpart of the fixed collar carried by said adjacent pipe.

PIERRE ERNEST MERCIER.

